Amino anthraquinone dyestuffs containing an amino stilbene group



Patented July 19, 1949 UNITED PATENT ,o F-ros AMINO ANTHREAQUINONE com TAINING AN AMINO STILBENE GRoUr W Curt GIVo gt, Union, N. J.,. assignor to 'diielai Aniline & Film Corporation, New York, N. Y., a corporation of Delaware I No Drawing. Application January 2, 1948,

Serial No. 361 o 2 Claims. (o1. 260367) The present invention relates to new dyestuffs of the anthraquinon'e series, more particularly to new derivatives of 1,4-diamino-anthraquinone-2- sul'fom'c acid of the general formula:

NHz ll SOs O H: C H- The capacity of the new dyestuffs to dye animal and nylon fibers from neutral bath is advanone of the fibers is sensitive to acids. For example, in the dyeing of mixed fibers of Wool and cotton or of nylon and cotton with one of the new dyestufis, the wool or nylon, as the case may be, is dyed in a bluish-red shade and the cotton, which remains undyed, is not tendered as would occur on using an acid bath for the dyeing. A preferred group of the dyestuffs for use in neutral dyeing are the ammonium salts of the dyestufis.

The new dyestuffs are prepared by condensing l-amino 4 halogena-anthraquinone-2-sulfonic acid (halogen may be chlorine or bromine) or an alkali metal salt thereof with 4,4'-diaminostilbene-2,2'-disulfonic acid or the corresponding 3,3-disulfonic acid or an alkali metal salt thereof. The condensation is carried out by heating an aqueous slurry of the reactants in the presence of a copper catalyst for the condensation such as cuprous chloride, and of an acid-binding agent such as calcined sodium carbonate. The reaction can be carried out with exclusion of air HO S from the hot reaction mass to obtain a product of highest purity, for which may be used an atmosphere of an inert gas such as nitrogen or carbon dioxide. N- kV-I The alkali metal and ammonium salts of the dyestuffs can be prepared in conventional manner by treating. thefree acid dyestuif with an aqueous solution ot a caustic alkali, e; a. sodium hydroxide, or of ammonia and heating the suspension of the dyestufi salt to dryness. The salts of the dyestufis may be warmed with dilute aqueous hydrochloric acid to split out the free acid dyestufi which, being insoluble in the acid, precipitates and can be collected by filtration.

The invention is further illustrated by the following specific example, to which, however, it is not to be limited. Parts are by weight.

tageous in the union dyeing of; textiles where Example A mixture of 111 parts 4,4'-diamino-stilbene- 2,2'-disulfonic acid with a purity of approximately 33.5% was slurried in 300 parts water. To this slurry was added 80.8 parts l-amino- 2sulfo-4-bromoanthraquinone, sodium salt. Anhydrous sodium carbonate was used to neutralize the slurry and make it slightly alkaline to litmus paper. Approximately 20 parts sodium carbonate anhydrous were required to do this. An additional 23.3 parts sodium carbonate anhydrous were added, making the mixture strongly alkaline to phenolphthalein paper. Then 4 parts cuprous chloride were added, and the mixture was refluxed until the reaction was completed. This required approximately 11 hours. The reaction mixture was allowed to cool to room temperature and filtered. The residue was washed with water, then slurried with boiling ethyl alcohol. The insoluble material was filtered OE, and the product washed with more ethyl alcohol and dried.

The product is the salt of the dyestufl which. preferably. is done by treatment with an of the probable formula: alkali metal sulflte in known way.

0 NE: NH: 0

s'om a OnH and dyes nylon a. bluish-red shade of good fast- I claim: ness properties. 1. An amino anthraqulnone compound of the Alternatively, the new dyestufls may be pregeneral formula:

V 0 NH. 7 7 NH: O

QgH no pared by condensing in the manner described and the alkali metal and ammonium salts above, the 4,4'-diamin0-stllbene-2,2'- or 3,3-dlthereof.

sulfonic acids with 1-amino-2A-dihalogeno-an- 2. An amino anthraquinone compound of the thraquinone and replacing the halogen atom formula:

0 NE! NH: (1?

I Joni (chlorine or bromine) in 2-position of the conand the alkali metal and ammonium salts densation product with the sulfonic acid group thereof.

CURT G. VOGT.

REFERENCES CITED The following referenices are of record in the Y file of this patent:

UNITED STATES PATENTS 2,156,887 Welnand May 2, 1939 

